what shutter speed are you shooting at? if you have it in "s" mode i am assuming that is a shutter priority mode in which case you would need to manually set your shutter speed. i am not familiar with sony DLSR's but if that "s" mode is a "sports" mode and you are shooting any sort of low lighting situation it is going to open up the lens and theen pick the highest shutter speed but will keep the exposure it's main concern and so if there isnt enough light it wont set the shutter fast enough to stop the action and so you will end up with blurry images. if you use shutter priority and set it to 1/1000 or 1/1250 th of a second then you shouldnt have any blur issues, but you might end up with underexposure issues if there isnt enough light.

On the Sony's I believe that the S mode is for shutter mode. On the dial I'm at 3200. I think that it will choose the apature(sp) based off what shutter speed that I choose. When I would have it in the "sports" mode it just didn't seem to keep up with the motion of the rider, especially on raley based tricks when the rider is really moving.

Sounds like an AF issue if you're already at 1/3200th. Everyone keeps talking about manually focusing when behind the boat but what people aren't realizing is that there is still quite a bit of distance changes and if you're at a fairly open aperture like f4 the rider will move in and out of the range of DOF.

If you're using AF it's always good to see what your cam is focusing on in any given image, it may not be where you think.

yeah, i don't believe you really need 1/3200 anyways. At that point your forcing yourself to A) use a larger (smaller number) aperture or B)increase the ISO which results in grainier pics. Personally, I would drop my shutter speed down to allow for a smaller (bigger number) aperture. Increasing your ISO also allows for a smaller (bigger number) aperture as well. Depending on your ISO I might increase that a little. 400 ISO is my happy zone. Shutter and Aperture priority are nice options but I tend to use full manual with Auto Focus mostly.

increasing the ISO increases sensitivity to light therefore allowing you to get proper exposure with less light but giving more Grain which is not necessarily bad. I know some may have a negative connotation to grain. It's a matter of preference really.

Also read up on your metering modes and your autofocus modes. your manual gives great pointers on what scenarios each mode would be used for. I give props to Sony for writing a rather plain english manual to help beginners. Not sure if their a700 and a900 have as easy to read manuals or not but they definitely cater my a200 manual to the beginning DSLR photographer. While photography classes taught me a lot. Moving to the digital realm added a ton more features they just don't teach in regular film photography.

Nate, great description, it is incredible how many people that start in digital photography don't understand these simple photography basics. It would be great if beginners went back and shot slide film. It gives you such a great appreciation for DSLR's.

very true Rich.....HOWEVER, what I was getting at, was that adjusting the other settings would allow for him to narrow down that aperture which does affect the depth of field. In turn, narrowing down his aperture would allow for more depth of field.

At 1/3200 he was probably not getting enough light in there unless he opened up the aperture.

I found it to be my common mistake when I got my DSLR to only change the shutter speed and aperture to get the exposure. You can imagine how difficult it was when I left the ISO on 100 all the time. It sort of sounds like what BBR was doing. Not necessarily the 100 ISO but because he doesn't specify his ISO settings. But if he upped his ISO to increase light sensitivity he could keep a higher shutter speed but narrow his aperture. Narrowing his aperture to increase his depth of field is what I was trying to accomplish.

Nate, it seems that you and I have the same camera and lens'. I think that I will look into that class that you linked up above so I can learn a bit more about it. The hard part for me is trying to learn the different ways that I need to change the settings from being in the boat, as opposed to being on the dock and having the riders moving toward you and away from you.

Nate, can you let me in on your settings secrets? Since we have the same camera I can start from there.